The newly-found footprints of theropod and ornithopod dinosaurs date reduction to the Early Cretaceous epoch, over 120 million years ago, when Australia become quiet connected to Antarctica.
Melissa Lowery and Anthony Martin look a dinosaur track. Image credit: Ruth Schowalter.
The Early Cretaceous dinosaur footprints were show veil within the Wonthaggi Formation south of Melbourne, Australia.
They consist of 18 tracks made by medium to mountainous theropods (0.8-1.9 m hip heights) and four tracks made by tiny ornithopod dinosaurs (40-forty eight cm hip heights).
“These various tracks are the finest evidence yet that these worn polar environments supported mountainous carnivores,” talked about Emory University’s Professor Anthony Martin.
“The mountainous theropods would seemingly hold fed on prey equivalent to smaller dinosaurs, fish and turtles.”
“The hip height of that theropod would hold been referring to the same because the stout height of a huge, common-day human.”
“The Australian speak of Victoria’s rocky coastal strata well worth the effect the feeble supercontinent Gondwana began to interrupt up around 100 million years ago, surroundings apart Australia from Antarctica.”
“The polar environment at the 2d become a rift valley with braided rivers.”
“Despite the proven truth that the mean annual air temperature become higher sooner or later of the Cretaceous than currently, sooner or later of the polar winters the ecosystems experienced deep freezing temperatures and months of darkness.”
“The Wonthaggi Formation has yielded one of the most finest assemblages of polar dinosaur physique fossils within the southern hemisphere, nevertheless these forms of remains are tiny fragments of bones and tooth.”
“These fragments may perchance presumably perchance presumably also just hold been carried to the positioning the effect they were buried by torrential spring floods.”
“Our obtain of so many theropod tracks, nonetheless, confirms that a vary of dinosaurs if truth be told lived and walked on the bottom the effect their bones were found.”
“Dinosaur tracks are if truth be told map more total at the positioning than we beforehand realized.”
The theropod footprints within the Wonthaggi Formation vary in size from 18 to 47 cm (7-18.5 inches).
They’re favorite by somewhat thin toes tipped with appealing claws.
The ornithopod footprints vary in size from 10 to 18 cm (4-7 inches).
The vary in sizes of the tracks suggests a mix of youth and grownup ornithopods and theropods.
“That indicates that these dinosaurs may perchance presumably perchance presumably also just hold nested and raised their young within the polar environment,” Professor Martin talked about.
The invention is reported in a paper within the Alcheringa, an Australasian Journal of Palaeontology.
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Anthony J. Martin et al. Polar dinosaur tracks of the Wonthaggi Formation (Lower Cretaceous), Victoria, Australia and their palaeontological significance. Alcheringa, an Australasian Journal of Palaeontology, published online September 8, 2024; doi: 10.1080/03115518.2024.2392498
